In the past, a self-report measure of sitting time, TV time, and/or computer time was the method typically used to assess sedentary time. More recently, wearable accelerometers have become the method of choice to improve measurement accuracy and precision. Numerous prediction methods are available
Chiaki Tanaka, Yuki Hikihara, Kazunori Ohkawara and Shigeho Tanaka
This study examined the potential relationship between participation in physical activity (PA) assessed by triaxial accelerometry and physical fitness testing, including health-related and skill-related parameters of fitness, in 136 Japanese preschoolers (65 girls and 71 boys, 5.5 ± 0.6 years). In partial correlation analyses, grip strength and 20m shuttle run test were positively correlated with time spent in physical activity ratio (PAR) ≥ 4. Better scores on standing long jump distance and jump over and crawl under tests were associated with lower sedentary time and greater moderate-to-vigorous PA time and PAR ≥ 4 time, and increased physical activity level. Moreover, 25m run speed was positively correlated with time spent in PAR ≥ 4 and locomotive activity. These findings suggest that development of both health-related (muscle strength and aerobic fitness) and skill-related fitness (power, agility and speed) may make engagement in PA easier for preschool children, although further research on the cause-effect relationship is needed.
Lisa H. Colbert, Charles E. Matthews, Dale A. Schoeller, Thomas C. Havighurst and KyungMann Kim
This study examined the intensity of activity contributing to physical activity energy expenditure in older adults. In 57 men and women aged ≥ 65, total energy expenditure (TEE) was measured using doubly labeled water and resting metabolic rate was measured using indirect calorimetry to calculate a physical activity index (PAI). Sedentary time and physical activity of light and moderate to vigorous (mod/vig) intensity was measured using an accelerometer. The subjects were 75 ± 7 yrs (mean ± SD) of age and 79% female. Subjects spent 66 ± 8, 25 ± 5, and 9 ± 4% of monitor wear time in sedentary, light, and mod/vig activity per day, respectively. In a mixture regression model, both light (β = 29.6 [15.6–43.6, 95% CI]), p < .001) and mod/vig intensity activity (β = 28.7 [7.4−50.0, 95% CI]), p = .01) were strongly associated with PAI, suggesting that both light and mod/vig intensity activities are major determinants of their physical activity energy expenditure.
Saori I. Braun, Youngdeok Kim, Amy E. Jetton, Minsoo Kang and Don W. Morgan
The purpose of this study was to determine if bone health at the femoral neck (FN) and lumbar spine (LS) can be predicted from objectively-measured sedentary behavior and physical activity data in postmenopausal women. Waist-mounted ActiGraph GT1M and GT3X devices were used to quantify levels of sedentary and moderate-to-vigorous intensity behavior during a 7-day period in 44 older females. Bone health (normal and osteopenia/osteoporosis) of FN and LS was derived from T scores generated using dual energy x-ray absorptiometry. Binomial logistic regression analysis indicated that sedentary time and number of breaks in sedentary behavior were significant predictors of osteopenia/osteoporosis at the FN, but not at the LS. Adherence to physical activity guidelines was not a significant predictor of bone health at the FN or LS. Our findings suggest that more frequent interruptions in sedentary behavior are associated with improved bone health in postmenopausal women.
Sofiya Alhassan, Ogechi Nwaokelemeh, Manneh Ghazarian, Jasmin Roberts, Albert Mendoza and Sanyog Shitole
This pilot study examined the effects of a teacher-taught, locomotor skill (LMS)- based physical activity (PA) program on the LMS and PA levels of minority preschooler-aged children. Eight low-socioeconomic status preschool classrooms were randomized into LMS-PA (LMS-oriented lesson plans) or control group (supervised free playtime). Interventions were delivered for 30 min/day, five days/week for six months. Changes in PA (accelerometer) and LMS variables were assessed with MANCOVA. LMS-PA group exhibited a significant reduction in during-preschool (F (1,16) = 6.34, p = .02, d = 0.02) and total daily (F (1,16) = 9.78, p = .01, d = 0.30) percent time spent in sedentary activity. LMS-PA group also exhibited significant improvement in leaping skills, F (1, 51) = 7.18, p = .01, d = 0.80). No other, significant changes were observed. The implementation of a teacher-taught, LMS-based PA program could potentially improve LMS and reduce sedentary time of minority preschoolers.
P. Margaret Grant, Malcolm H. Granat, Morag K. Thow and William M. Maclaren
This study measured objectively the postural physical activity of 4 groups of older adults (≥65 yr). The participants (N = 70) comprised 3 patient groups—2 from rehabilitation wards (city n = 20, 81.8 ± 6.7 yr; rural n = 10, 79.4 ± 4.7 yr) and the third from a city day hospital (n = 20, 74.7 ± 7.9 yr)—and a healthy group to provide context (n = 20, 73.7 ± 5.5 yr). The participants wore an activity monitor (activPAL) for a week. A restricted maximum-likelihood-estimation analysis of hourly upright time (standing and walking) revealed significant differences between day, hour, and location and the interaction between location and hour (p < .001). Differences in the manner in which groups accumulated upright and sedentary time (sitting and lying) were found, with the ward-based groups sedentary for prolonged periods and upright for short episodes. This information may be used by clinicians to design appropriate rehabilitation interventions and monitor patient progress.
Stephanie L. Stockwell, Lindsey R. Smith, Hannah M. Weaver, Daniella J. Hankins and Daniel P. Bailey
. Sedentary behavior is defined as any waking behavior characterized by an energy expenditure of ≤1.5 metabolic equivalents while in a sitting, reclining, or lying posture. 4 It has been reported that children aged 10–14 years engage in approximately 7 to 8 hours of objectively measured sedentary time each
Sheri J. Hartman, Catherine R. Marinac, Lisa Cadmus-Bertram, Jacqueline Kerr, Loki Natarajan, Suneeta Godbole, Ruth E. Patterson, Brittany Morey and Dorothy D. Sears
reclining posture (excluding sleeping). Common forms of sedentary behaviors include sitting for work and during transportation, eating, and leisure (eg, watching television or relaxing). Sedentary time is associated with higher numbers of comorbid conditions, higher tumor stage, and greater severity of
Kelly R. Evenson, Amy H. Herring and Fang Wen
Few studies measure physical activity objectively or at multiple time points during postpartum. We describe physical activity at 3- and 12-months postpartum among a cohort of women using both self-reported and objective measures.
In total, 181 women completed the 3-month postpartum measures, and 204 women completed the 12-month postpartum measures. Participants wore an ActiGraph accelerometer for 1 week and completed in-home interviews that included questions on physical activity. A cohort of 80 women participated at both time points. Poisson regression models were used to determine whether physical activity differed over time for the cohort.
For the cohort, average counts/minute were 364 at 3-months post-partum and 394 at 12-months postpartum. At both time periods for the cohort, vigorous activity averaged 1 to 3 minutes/day, and moderate activity averaged 16 minutes/day. Sedentary time averaged 9.3 hours at 3-months postpartum and 8.8 hours at 12-months postpartum, out of a 19-hour day. Average counts/minute increased and sedentary behavior declined from 3- to 12-months postpartum.
Interventions are needed to help women integrate more moderate to vigorous physical activity and to capitalize on the improvements in sedentary behavior that occur during postpartum.
Meredith C. Peddie, Claire Cameron, Nancy Rehrer and Tracy Perry
Interrupting sedentary time induces improvements in glucose metabolism; however, it is unclear how much activity is required to reduce the negative effects of prolonged sitting.
Sixty-six participants sat continuously for 9 hours except for required bathroom breaks. Participants were fed meal replacement beverages at 60, 240 and 420 min. Blood samples were obtained hourly for 9 hours, with additional samples collected 30 and 45 min after each feeding. Responses were calculated as incremental area under the curve (iAUC) for plasma glucose, insulin and triglyceride. Participants wore a triaxial accelerometer and a heart rate monitor. Energy expenditure was estimated using indirect calorimetry.
After controlling for age, sex and BMI, every 100 count increase in accelerometer derived total movement was associated with a 0.06 mmol·L-1·9 hours decrease in glucose iAUC (95% CI 0.004–0.1; P = .035), but not associated with changes in insulin or triglyceride iAUC. Every 1 bpm increase in mean heart rate was associated with a 0.76 mmol·L-1·9 hours increase in triglyceride iAUC (95% CI 0.13–1.38).
Accelerometer measured movement during periods of prolonged sitting can result in minor improvements in postprandial glucose metabolism, but not lipid metabolism.